For this particular exercise for the California State University at Monterey Bay, the client asked for a version of the illustrative plan with the roof plan shown and building shadow for depth.
(Above) Google Earth Shot. Locate the project area that shows the building and contextual site elements. CSUMB sits in a flat site that is surrounded by groves of trees and open brush. Some of the landscape forms and parking layouts had changed during the design process, but all we want for this exercise is the actual building to extract from.
(Above) Turn on 3D Building View. In the tool/navigation bar in Google Earth, turn on the 3D view in order to extrude the building view. This is helpful because when a 3D model is built for Google Earth view, these buildings tend to show a bit more detail especially in the birds-eye view mode.
(Above) Overlay Google Earth View. In Google Earth, save the image at the highest image quality and bring into your illustrative plan in Photoshop or Illustrator.
(Above) Clip and Drop Shadow in Photoshop. In Adobe Photoshop, clip out and isolate the building to be inserted into your illustrative plan. On the building layer, double click the layer to access the layer style panel. By clicking on the Drop Shadow style, you can adjust the depth/height of the shadow which gives the illusion of the building shadow over the site landscape. You can change the angle, opacity, spread, and even color in this panel. Be sure that the building shadow matches the existing shadows of the trees so everything is consistent.
(Above) Final Touches. In Photoshop, you can adjust the filters, layer order, and opacities to balance out the overall illustrative site plan. With filters, you can make the roof plan look like a sketch, watercolor, paint daubs, etc. You can then export the final artwork as a jpeg to insert into a presentation or send to your client for their use.
The overall process should only take 30 minutes to an hour if the source files are readily available and you have good understanding of photoshop and layer management. I hope you found this blog helpful and informational. If you have specific questions about any particular parts of this process, just send me a message.